EDEN PRAIRIE, Minn. -- With the 2014 NFL draft over, the Minnesota Vikings got to work on Saturday evening, signing a group of undrafted free agents to join the 10 players they took in the draft.

The Vikings announced they had agreed with 15 undrafted free agents as of Saturday night, though the players still have to pass physicals before they'll be able to participate in the team's rookie camp next week. The most prominent name in the group is former Northwestern quarterback Kain Colter, who led the effort of Northwestern players to form a union and argue that they should receive the basic rights of employees.

If all 15 players' contracts are finalized, the Vikings would have 93 players under contract, and would need to make several roster moves to get down to the NFL's 90-contract limit.

"There are guys on the bottom end of our roster," general manager Rick Spielman said. "We feel some of these college free agents are going to have a chance to come in and compete and then there may be a couple roster moves to make sure we get to 90 players. The draft picks are going to count because this goes up to 90 players but our college free agents won’t sign their contracts till they get in. Once they get in and pass their physicals, will then make sure we are at 90 players where we need to be."